(1) Field of the Invention
The present invention generally relates to remote measurement sensors and more particularly to a device for measuring unwanted electric and magnetic field induced voltages in a test lead connected to a remote measurement sensor.
(2) Description of the Prior Art
Alternating magnetic fields are usually measured with a sensor coil. Frequently, the sensor coil is a remote sensor inside a test fixture of high magnetic attenuation while the test lead from the remote sensor to the measuring equipment must pass through a strong magnetic field environment surrounding the test fixture. In these test configurations, faulty measurement readings can be created by voltages induced in the test lead exposed to the strong magnetic field. Generally, a sensor is considered to be a remote sensor when the sensor is 6 feet or more away from the measuring equipment.
Faulty readings can also be created by the electric field coupling caused by the voltage potential between the test fixture and the remote sensor or test lead. Quantification of this electro-magnetic field induced interference in the test lead is especially critical when attempting to measure low level alternating current (AC) signals.